X-ray CT system for producing projective and tomographic phase contrast images

Abstract

An X-ray CT system is disclosed for producing tomographic phase contrast and absorption images. In at least one embodiment, the system includes a gantry, including a stationary stator and a first rotor supported on the stator and rotates relative to the stator about a system axis, at least one X-ray source detector system that can rotate about a patient and a system axis and is arranged on the first rotor, and at least one set of X-ray optical gratings for determining phase contrast. According to at least one embodiment, the at least one set of X-ray optical gratings is arranged such that it can be displaced relative to the first rotor of the gantry.

1. An X-ray CT system for producing tomographic phase contrast and absorption images, comprising:
 a gantry, including a stationary stator and a first rotor supported on the stator to rotate relative to the stator about a system axis; 
 at least one X-ray source detector system to rotate about a patient and a system axis and arranged on the first rotor; and 
 at least one set of X-ray optical gratings for determining phase contrast, wherein the at least one set of X-ray optical gratings is arranged to be displaced relative to the first rotor of the gantry. 
 
     
     
       2. The X-ray CT system as claimed in  claim 1 , wherein the at least one set of X-ray optical gratings, in the operating state, covers only a part of the detector. 
     
     
       3. The X-ray CT system as claimed in  claim 1 , wherein, in addition to the rotor on which at least one X-ray source and at least one detector are fastened, the gantry Includes a displacing apparatus on which the X-ray optical gratings are arrangeable on the beam path, are fastened, and with the aid of which the gratings are displaceable from the beam path and into the beam path of the X-ray source. 
     
     
       4. The X-ray CT system as claimed in  claim 3 , wherein the displacing apparatus on which the X-ray optical gratings, arrangeable in the beam path, are fastened, is designed in the shape of a circular segment and fastened on the first rotor. 
     
     
       5. The X-ray CT system as claimed in  claim 3 , wherein the displacing apparatus on which the X-ray optical gratings, arrangeable in the beam path, are fastened, is designed as a second rotor. 
     
     
       6. The X-ray CT system as claimed in  claim 1 , wherein the X-ray optical gratings are fastened to be displaceable in the direction of the system axis. 
     
     
       7. The X-ray CT system as claimed in  claim 1 , wherein the X-ray optical gratings are designed to be displaceable in the direction of rotation relative to the first rotor. 
     
     
       8. The X-ray CT system as claimed in  claim 2 , wherein the X-ray source includes a diaphragm to adapt the emitted beam cone to the extent of at least one of the X-ray optical gratings and the overall detector. 
     
     
       9. The X-ray CT system as claimed in  claim 1 , wherein at least one X-ray source includes a source grating. 
     
     
       10. The X-ray CT system as claimed in  claim 1 , wherein a first beam path is provided exclusively for absorption measurement and a second beam path, arranged offset in the direction of the system axis, is provided for phase contrast measurement. 
     
     
       11. The X-ray CT system as claimed in  claim 10 , wherein the gantry includes a second rotor, one detector being arranged on the first rotor for absorption measurement, and a second detector being arranged on the second rotor exclusively for phase contrast measurement with the aid of the set of X-ray optical gratings. 
     
     
       12. The X-ray CT system as claimed in  claim 10 , wherein a dedicated X-ray source is arranged on each rotor. 
     
     
       13. The X-ray CT system as claimed in  claim 2 , wherein the X-ray optical gratings are fastened to be displaceable in the direction of the system axis. 
     
     
       14. The X-ray CT system as claimed in  claim 2 , wherein the X-ray optical gratings are designed to be displaceable in the direction of rotation relative to the first rotor. 
     
     
       15. The X-ray CT system as claimed in  claim 3 , wherein the X-ray optical gratings are fastened to be displaceable in the direction of the system axis. 
     
     
       16. The X-ray CT system as claimed in  claim 3 , wherein the X-ray optical gratings are designed to be displaceable in the direction of rotation relative to the first rotor. 
     
     
       17. The X-ray CT system as claimed in  claim 3 , wherein the X-ray source includes a diaphragm to adapt the emitted beam cone to the extent of at least one of the X-ray optical gratings and the overall detector. 
     
     
       18. The X-ray CT system as claimed in  claim 2 , wherein at least one X-ray source includes a source grating. 
     
     
       19. The X-ray CT system as claimed in  claim 3 , wherein at least one X-ray source includes a source grating. 
     
     
       20. The X-ray CT system as claimed in  claim 11 , wherein a dedicated X-ray source is arranged on each rotor.